Carburetor



E. G. GILSON.

CARBURETOR.

APPLICATION FILED AUG.26. I9I9 1,407,024, Patented Feb. 21, 1922.

His lttorneg.

UNITI-:ng STATES PATENT OFFICE,

EMERY e. G1Lso1v,or 'scHENEoTAEx NEW Yonx, assreivon To GENERAL ELECTRIC CQMPANX, A-coEPoRA'rIoN or NEW Yonx.

cAnnUnE'ron. n

To all whom ama/y concern:

Bc itknown that I, EM'ERY Gj.A G rineoiv, a citizenv of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements in` Carburetors, of which the following is a specification.

The present invention relates to carburetors such as are used in connection with in- Referring' to the drawing,'5 indicates a fuel chamber of a carburetor and Ganannular float therein which is connectedby a lever 7 to a valve 8' for controlling the admission of fuel through fuel inlet 9 to chamber 5. lFuel maybe fed to inlet 9`from any' suitable source of supply. Float 6 serves to.

' maintain aconstant level of fuel in chamber' inthe well'understood Vmanner and may be adjusted to maintain the desired. level by adjusting the valve 8.

The `upper wall of fuel chamber 5is curved downwardly so it projects into the center of fioat 6 and at its lowermost part terminates in a wall 12. The lower surface of Wall 12 is flat and depending therefromk is a shield ring 13. The upper surface` of wall 12 is curved as shown. andy is provided atV its central portion with a cone-shaped projection 15. 16 indicates the upper lwall of the carburetor and projecting` through an opening in it isa mixin tube .17, the outer end of which is adapte. yto be connected to the intake manifold of an engine as is wellv understood. of mixing tube 17 terminates adjacent to wall 12 at the base of cone-shaped projection 15 and on its end is aring 19, which may or may not be an integral part of tube 17, the outer surface of which defines with curved wall 11, an annular venturi shaped air passage 20. Surrounding mixing tube The inner or lower endV Specification of Letters Patent. vPatented Feb. .21, 1922.5 YAppuezmon ined august 26, 191e. seiiainq. 319,980.' i

17 is an air. chamber 21 to whichfair is 'admitted through an air'inlet 22.

Fuel is admitted'from fuelchamber 5 to mixing tube 17 through a plurality of small orifices 23 located in 'wall 12 at the base of' cone-shaped vprojection 15, the yportion of wall 'whichdelines the orifice being'very thin. This locatesorifi'ces 23 at the throat ofthe venturi-shaped air passa e 20. Twoy or more 'orifices 23 may be uti ized'spaced around the base of projection, 15 and they may be provided by forming orifices in very think ortions lof wall 12 as indiciwzted'atf23a 1n Fig, 3 or by, providingl'ioles'24in wall 1'2 over whichare 4fastened thilr plates which 4contain orifices 23. f By providing such orifices 23 or 23a throughwhich fuel is fed the proportion'o'f fuel to air made-by the carburetor will be substantially uniforml through lthe bottom wallof fuel' chamber 5` and is fastened therein bywash'ers 27 and a. nut 28. Through thelongitudinalfcenter of rod 26 is af pass'age29 which at its upper end communicates'vv'ith a lsmall pass'age'()y through ycone-shaped projectionf. The purpose of this isv to .provide an overflow or drainl for 'fuel in case the carburetor [becomes flooded. .The 4outer end ofL passage 29 may Vopen to atmosphere or may be connect,- ed with some suitable receptacle. i

Mixing tube 17 is preferably divided lon-` gitudinally into two parts or passages by a partition 31 and in each of saidjpassagesis arranged a valve. 32 for. controllingthejflow of mixture from the mixing .tube to the fengine. `Valves 32 are pivoted therein atthe edgeremote from partitiony 31. By this means as the valves are opened the mixture passes along close to the surface of partition 31. Any suitablefmeans such asthe feds. 32? may be Provided] for operating valves 32in the desiredI sequence. By 'pro-l vidi'ng twoseparate passages in the mixing tube it will be seen that in operation first one passage may be opened and then, as the load becomes greater, the other. This gives in substance the advantage of a smaller carburetor for starting and for use at light loads and a larger carburetor for heavy loads and results in substantial economy in the use of fuel. i

I also. .preferably :arrange v'the carburetor so that the throat ofthe'annular venturi shaped passage 2O may be adjusted and to this end I arrange the mixing tube and the A wall 12 so they may be moved toward and away 'from each other. KAs one manner of doing this, I may make Athey mixing tube A17 in two parts as shown, one of which telescopes within the other as indicated at1733, and provide a suitable adjusting `means asia rack 34 and pinion 35 whereby the lower end of the mixing tube may be moved away from and toward wall 12. f The pinion 35 may be arranged to be turnedinany suitable manner; in fthe case fof an automobile-'I pref erably arrange` a suitable member located within reachof the driver so that he mayadf just the same while vthe car is running.` In starting the end of the mixing tube willbe moved closer to wall. 12 so as to reduce the area ofthe venturi throat which 4will give an increased suction effect. After the engine is started the end ofthe mixing tube may be moved slightly fartheraway from wall 12 thereby increasing the area ofthe throat of the venturi passage with the result that the suction will be less and the ,mixture` thinner.

In operation, the float G and valve 8 are adjusted so ythat'when the engine-is idle a fuel level will be establishedA which, is slightlyabove the orifices'23., When the engine is operating air is drawnin through air inlet 422A to annular chamber 21 v'from which it passes in an `annular sheet down throughfventuri shaped passage 20, hence ata right angle across the 'orifices-23 and then upward intojmixing tube 17., Vhen starting the engine, as fuel is present above orifices 23 such fuel' will be taken up very readily by the air, carried along into the mixing tube, and mixed with thel air. This assures a sufiiciently rich mixture to make starting easy. After the engine is started and the carburetorhas been used a short time, the ,fuel above orifices 23 willhave been used up. The passage of the air across orifices 23 will then draw fuel up through themV for mixing with the` air and due to the arrangementlof the orifices a very uniform mixture of the desired richness maybe maintained at vall speeds. The arrangementy therefore gives `automatically a richmixtureffor `starting and a leaner mixture for running. At any time the richness of the mixture'may be adjusted by moving the innerend of mixing tube 17 `toward or away from wall 12. The fact that air enters the mixing tube as an annular sheet coming in from all sides andflowing 'at a right angle acrossforifces 23 'results in the fuel being initially well distributedrthrough the air.

In accordance with the'provisions 0f the patent statutes, I have described the prin- Lciple'ofoperation of my invention, together with the apparatus which I now consider the best embodiment `tlier'eof, but I desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means .such 'as come `within the scope ofthe appended claims. `g t f What I claim as new and desire to secure by 1Letters Patent is L- t 1. In a carburetor, a fuel chamber having a top wall which curves inwardly to form a recess,- a' mixing tube which depends into: said recess and forms .with the surface of:Y

the top` wall an annular venturi-shaped air passage, a plurality ofthin portions in the wallv at the bottom of saidrecess said portions being provided with orifices through which fuelis fed fromthe fuel chamber to the mixing tube, said orifices being spaced around the lower end ofthe mixing tube and located at the throat of the venturi-shaped passage, and'means for maintaining a substantially' 4constant level of -fuel in the fuel chamber slightly above the` plane of' said orifices whereby a' small supply of fuel will be providedat the throat of the venturishaped vpassage above the orifices for starting. ,Y l A f j 2. In acarburetor, a fuel chamberhavinga top wall which curves inwardly to form a' recess,a mixing tube which depends ,into

said recess and forms with ,the surface of tne top Vwall an annular venturi-shaped air passage, means forming orifices in the Wall at the bottom ofsaid recess through which fuel is fed from the yfuel chamber to the mixing tube, said means comprising thin. plates having openingsr therein, said orifices being spaced aroundthe lower end of the mixing tube and located at thethroat of the ven turi-shaped passage,and means for maintaining 'a substantial constant level ofy fuel in thefuel chamber slightly above the plane of said orifices whereby asmall supply of fuelwill be provided at the throat yof the venturi`-shaped `:passage above the orifices for starting. l

In witness whereof, I have hereunto set myhand this 25th day of August, 1919.

EMERY o. GILsoN. 

